I have those fonts installed, but whether The way you produce the crash is
to visit a file with C-x C-f.

;; Commenting this line is makes the crash go away, 'prepend also makes the
crash go away
(set-fontset-font "fontset-default" 'unicode "Apple Color Emoji" nil
'append)

(require 'all-the-icons)

;; This is the actual culprit. Even with 'append, not inserting the icon
into the mode line
;; after change major mode will not produce a crash.
(add-hook 'after-change-major-mode-hook
            (lambda ()
              (let* ((icon (all-the-icons-icon-for-mode major-mode))
                     (face-prop (and (stringp icon) (purecopy
(get-text-property 0 'face icon)))))
                (when (and (stringp icon) (not (string= major-mode icon))
face-prop)
                  (setq mode-name icon)))))


On Sat, Jun 16, 2018 at 12:45 PM, Alan Third <alan@idiocy.org> wrote:

> On Fri, Jun 15, 2018 at 01:51:58AM +0100, Jimmy Yuen Ho Wong wrote:
> > I've finally isolated my problem with this code block:
> >
> > (set-fontset-font "fontset-default" 'unicode "Apple Color Emoji" nil
> > 'append)
> >
> > (use-package all-the-icons
> >   :config
> >   (add-hook 'after-change-major-mode-hook
> >             (lambda ()
> >               (let* ((icon (all-the-icons-icon-for-mode major-mode))
> >                      (face-prop (and (stringp icon) (purecopy
> > (get-text-property 0 'face icon)))))
> >                 (when (and (stringp icon) (not (string= major-mode icon))
> > face-prop)
> >                   (setq mode-name icon))))))
>
> I can’t get all-the-icons to work (it’s looking for memoize?), but I
> notice it comes with a bunch of fonts.
>
> Do you have those fonts installed? If so, does completely removing the
> set-fontset-font line for Apple Color Emoji still result in a crash?
> --
> Alan Third
>